<!DOCTYPE html>
<link rel=author href="mailto:jarhar@chromium.org">
<link rel=help href="https://drafts.csswg.org/css-transitions-2/#transition-behavior-property">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/css/css-animations/support/testcommon.js"></script>

<div class=testcase id=discrete>Allow discrete</div>
<div class=testcase id=normal>No discrete</div>

<style>
.testcase {
  float: left;
  width: 100px;
  height: 100px;
  transition: all 1s;
}
#discrete {
  transition-behavior: allow-discrete;
}
.animated {
  float: right;
}
</style>

<script>
promise_test(async () => {
  await waitForAnimationFrames(2);
  // Regression test for https://crbug.com/1518561
  normal.classList.add('animated');
  const normalAnims = normal.getAnimations();
  assert_equals(normalAnims.length, 0,
                "Should not start a discrete property transition");

  discrete.classList.add('animated');
  const anims = discrete.getAnimations();
  assert_equals(anims.length, 1,
                "Should start a discrete property transition");
  assert_equals(anims[0].transitionProperty, 'float');
}, 'transition-behavior:allow-discrete should animate discrete properties.');

promise_test(async t => {
  const div = addDiv(t, {
    style: 'transition: all 1s normal, float 1s allow-discrete; float: left',
  });
  getComputedStyle(div).float;

  div.style.float = 'right';
  const anims = div.getAnimations();
  assert_equals(anims.length, 1,
                "Should start a discrete property transition");
}, 'transition-behavior:allow-discrete overlaps the previous normal value.');

promise_test(async t => {
  const div = addDiv(t, {
    style: 'transition: all 1s allow-discrete, float 1s normal; float: left',
  });
  getComputedStyle(div).float;

  div.style.float = 'right';
  const anims = div.getAnimations();
  assert_equals(anims.length, 0,
                "Should not start a discrete property transition");
}, 'transition-behavior:normal overlaps the previous allow-discrete value.');

promise_test(async t => {
  const div = addDiv(t, {
    style: 'transition: position 1s allow-discrete; position: relative',
  });
  getComputedStyle(div).position;

  div.style.position = 'static';
  assert_equals(div.getAnimations().length, 1,
                "Should start a discrete property transition");

  div.style.transitionBehavior = "normal";
  div.style.position = 'absolute';
  assert_equals(getComputedStyle(div).position, "absolute");
  assert_equals(div.getAnimations().length, 0,
                "The running transition should be cancelled");
}, 'transition-behavior changed to normal should stop the running discrete ' +
   'transitions.');

promise_test(async t => {
  const div = addDiv(t, {
    style: 'transition: clip-path 5s normal; clip-path: circle(50px)',
  });
  getComputedStyle(div).transition;

  div.style.clipPath = "circle(farthest-side)";
  assert_equals(getComputedStyle(div).clipPath, "circle(farthest-side)");
  assert_equals(div.getAnimations().length, 0,
                "Should not start a transition of discrete animation values");

  div.style.transitionBehavior = "allow-discrete";
  div.style.clipPath = "circle(200px)";
  assert_equals(getComputedStyle(div).clipPath, "circle(farthest-side)");
  assert_equals(div.getAnimations().length, 1,
                "Should start a transition for discrete animation values");
}, 'transition-behavior:allow-discrete should animate for values fallback to ' +
   'discrete animations.');

promise_test(async t => {
  const div = addDiv(t, {
    style: 'transition: clip-path 5s allow-discrete; clip-path: circle(50px)',
  });
  getComputedStyle(div).transition;

  div.style.clipPath = "circle(farthest-side)";
  assert_equals(getComputedStyle(div).clipPath, "circle(50px)");
  assert_equals(div.getAnimations().length, 1,
                "Should start a transition for discrete animation values");

  div.style.transitionBehavior = "normal";
  div.style.clipPath = "ellipse()";
  assert_equals(getComputedStyle(div).clipPath, "ellipse()");
  assert_equals(div.getAnimations().length, 0,
                "The running transition should be cancelled");
}, 'transition-behavior:normal should cancel the running transitions whose ' +
   'animation values are not interpolatable');

</script>
